Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/64576
COMPARTIR / EXPORTAR:
logo share SHARE logo core CORE BASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE

Invitar a revisión por pares abierta
Título

Dynamic behavior in solution of the trans-hydridodihydrogen complex [OsHCl(ν2-H2)(CO)(PiPr3)2]: Ab initio and NMR studies

AutorBakhmutov, Vladimir I.; Esteruelas, Miguel A. CSIC ORCID; Lledós, Agustí; Modrego, Francisco J. CSIC ORCID; Oro, Luis A. CSIC ORCID; Sola, Eduardo CSIC ORCID CVN
Fecha de publicación1996
EditorWiley-VCH
CitaciónChemistry - A European Journal 2(7): 815-825 (1996)
ResumenReaction of complex [OsHCl-(CO)(PiPr3)2] (1) with hydrogen gives the trans-hydrodidodihydrogen complex [OsH-Cl(π1-H2)(CO)(PiPr3)2] (2). The H-H distance in the dihydrogen ligand, determined by variable- temperature 1H T1 measurements, is 0.8 Å. The fast-spinning nature of the dihydrogen ligand of 2 has been deduced by evaluating the deuterium quadrupole coupling constant for the π2-D2 ligand of [OsDCl(π2-D2)(CO)(PiPr3)2] ([D3]2). Measurements of the equilibrium constants for formation of 2 (K) give ΔH(±) = -14.1 ± 0.5 kcal mol-1 and ΔS(±) = -30 ± 1 e.u. An equilibrium isotope effect K(d)/K of 2.8 is found for this reaction. The activation parameters for the H2 loss from 2 are ΔH(±) = 14.6 ± 0.2 kcal mol-1 and ΔS(±) = 9.9 ± 0.5 e.u. Hydrogen exchange between the hydrido and π2-H2 ligands of 2 takes place at a slow rate (k2/(obs)) at high temperatures. Activation parameters ΔH(±) = 17.4 ± 0.5 kcal mol-1 and ΔS(±) = 1.3 ± 1 e.u., and a kinetic isotope effect (k2/(obs)/k(2d)/(obs)) of 4.6 at 333 K have been determined for this exchange. Ab initio calculations on the model system [OsH- Cl(H2)(CO)(PH3)2] confirm that the trans-hydridodihydrogen complex [OsH- Cl(π2-H2)(CO)(PH3)2] (4) is the most stables species (r(HH) = 0.84 Å). In addition, a cis-hydridodihydrogen complex 5, with a relative energy of 13.8 kcal mol-1, occupies a local minimum in the potential hypersurface. The energy of other possible trihydrido isomers have also been evaluated. On the basis of the thermodynamic and kinetic data, and the results of the ab initio calculations, the possible mechanism for the H/π2-H2 exchange is discussed.
URIhttp://hdl.handle.net/10261/64576
DOI10.1002/chem.19960020714
Identificadoresdoi: 10.1002/chem.19960020714
issn: 0947-6539
e-issn: 1521-3765
Aparece en las colecciones: (ICMA) Artículos




Ficheros en este ítem:
Fichero Descripción Tamaño Formato
accesoRestringido.pdf15,38 kBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo

CORE Recommender

SCOPUSTM   
Citations

49
checked on 20-mar-2024

WEB OF SCIENCETM
Citations

51
checked on 28-feb-2024

Page view(s)

261
checked on 29-mar-2024

Download(s)

82
checked on 29-mar-2024

Google ScholarTM

Check

Altmetric

Altmetric


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.